The Business of Toxicity
by Awareness Bringer
Summary: What if Luffy was a smarter, Modified Human? Please read the bolded words for challenge story details.


**Originally, I wanted this to be a one-shot featuring Luffy with two to three Devil Fruit powers, then I decided that it would be a challenge story featuring Luffy becoming a Modified Human like Reiju and then much smarter before the age of seventeen. Just follow along and you'll see where I'm getting at.**

 **No unnecessary bashing: seeing characters grow up and show hidden strengths is all good until it looks like the writer is purposefully making the character in question look like an unlikable nuisance at best and a complete villain at worst. Trust me, it's best to show both the positives and negatives of those in a story. And since this is an AU, I'm working forward to some people growing up differently, especially in a positive manner.**

 **No slash: I try not to judge people who have different "bonding" preferences compared to mine, but I really don't think that characters that weren't listed as canonically yaoi in nature should be depicted as such. Not that I like gender bending much either.**

 **Keep the content at a controlled level: meaning that it's probably best to be mindful of which direction the story/stories will go. I like straight lemons as much as the next fellow, but given how things all are iffy on certain websites like FFN, it would probably be wise to just walk first before jumping.**

 **Don't shy away from asking me for advice or beta reading: however, I won't dictate your execution as it should ultimately be your decision. I'm doing fine with it so far with digemsmack over his Fairy Tail story which I gave my patronage for, Ascension of the Second Apocalypse, even if he's silent right now.**

 **Disclaimer: I don't own One Piece, Eiichiro Oda does.**

 **[TBOT]**

 **The Business of Toxicity**

 **[TBOT]**

Within the jungles of Dawn Island, a fifteen-year-old Luffy spent his time retracing the steps he had already taking in the past, fighting wild animals of large sizes to both train himself as well as feast on the meat on their bones, and finding poisonous plants to consume the poisons out of them. While it was admittedly lonely without a sworn brother or good pirate for him to talk to, and even more boring since he had two years yet to go on his own pirate voyage, Luffy wasn't discouraged and instead, looked forward to becoming King of the Pirates.

Looking back on his youth, he remembered how his poison-based powers first came to him. He was a seven-year-old boy at the time when he got enraged at local mountain bandits badmouthing his friends in the Red Hair Pirates to the point he returned their taunts straight back at them when it was clear the captain, Shanks, wasn't going to do anything about it, but only received a sword slash as a result. After Shanks and his crew dealt with the bandits for hurting him, they then worked with Luffy's villagers in healing his wounds, even bringing out a case of blood vials they had robbed off from a North Blue group called Germa 66. Although Shanks had his concerns about the blood samples in spite of them being of the same blood type as Luffy, he ultimately used one of the vials when Luffy needed a donation to keep himself alive, but upon waking up and flexing his muscles, found out he had the power to secrete poison from his body as well as safely consume it.

It caused quite a stir in the village, especially when they came to the conclusion that Luffy's new abilities weren't the result of a Devil Fruit. Nonetheless, he parted on good terms with the Red Hair Pirates, promising Shanks himself that he would raise himself into the same title and role Gold Roger played, and was given Shanks' prized straw hat which Luffy kept with him since then. Eight years passed, and Luffy felt he was growing stronger with each year. While he still hadn't learned how his poison powers came to him, Luffy wasn't necessarily bothered by it, and kept moving forward.

It was on that day, though, that he felt that he was being watched by someone or something unseen. As Luffy was about to get a grasp of the situation, he then found himself jumped by a tall, curly horned man with pale white skin and a gaseous look. When Luffy tried to fight back, the horned man cackled. "Now let's not be hasty, brat!" He gloated. "It took me a good amount of time to find Judge's pet project, and if there's one that's never going to happen, is for Caesar Clown to be denied!"

Luffy had no idea what Caesar was going on about, but he refused to go down without a fight, regardless. Finally getting Caesar off of himself, Luffy threw out a poisonous punch at him, but it passed through Caesar instead of hitting him. Caesar cackled again. "Stupid brat! I ate the Gas-Gas Fruit! You won't be able to even give me a scratch!"

It was then that Luffy smirked. "Gas, huh? Like poisonous gas?"

Caesar's own smirk then vanished when he absorbed the implication and groaned in annoyance. "I knew I should've put more preparation in this."

As he then tried to escape, Luffy took a great inhale and swallowed a protesting Caesar in an instant. In that moment, Luffy experienced an enormous spasm throughout his whole body before it finally cooled down. Exhaling, Luffy commented. "Yeesh, I don't what that was about, but I hope it doesn't happen again."

"That makes two of us." A familiar voice angrily agreed.

Yelping in shock, Luffy turned to see that Caesar outside of his body and looking extremely mad.

"I ate you!" Luffy snapped. "How are you still here?!"

"I'm not exactly here, stupid!" Caesar snapped back. "I'm talking to you from your head!"

Luffy then looked somewhat afraid. "Does that mean I've gone crazy?" He then thought it over before saying. "Unless, when I swallowed you up with my Modified Human power, it added your consciousness and being to my body and mind. Yeah that makes better sense." He then looked shocked again. "But how do I know that?"

Caesar scoffed. "Probably because when absorbed me, you also absorbed a degree of my genius intellect as well." He then raised an eyebrow in interest. "So, what do you "remember" of my reason for coming here?"

Luffy thought hard for a bit before answering. "You heard rumors of your scientific rival, Germa King Vinsmoke Judge, taking blood samples from one of his Modified Human experiments with the plan to donate those blood samples to people of the same blood type as part of an experiment. Shanks' robbery notwithstanding. When you figured that Germa 66's eyes and ears were a bit inattentive, you came to Dawn Island after hearing about a Modified Human being here."

Caesar nodded. "Correct, but now we're stuck with each other, whether we like it or not." He then seethed. "And I seriously don't like it."

Luffy frowned before finding himself laughing. "Well, it might now be what I had in mind about getting experience, but I'll might as well take it." He then frowned heavily at Caesar again. "Now play ball, or else."

 **[TBOT]**

 **When I decided to make this challenge story, I kind of debated of making sure Luffy got a Devil Fruit, even if it wasn't his canonical one, but while the Gum-Gum Fruit is useful and might play a vast importance in the eventual finale of One Piece, it's not every story you see Luffy being capable of fighting Sea Kings in their own turf like in the Marine Luffy story To Protect Everything, which is why instead of Shanks bringing a Devil Fruit, I had him bring a "special cargo" of the Germa Kingdom's that would lead to Luffy becoming a Modified Human similar to Reiju and later on, "inheriting" Caesar's brilliance after taking a "slurp" of his poisonous contents. They do share the same blood type with Jimbei, Vivi, and each other, after all. And of course, I have no desire of seeing Luffy becoming just as malicious as Caesar, or even too mature, just smarter and maybe more aware about women with a fair degree of self-control, if you must know. Just let the possibilities soak in for a bit and let me know what you're thinking.**

 **I was a bit on the fence on whether to let Caesar escape for obvious reasons, but while SMILEs made by the Donquixotes and sold to the Beasts Pirates are an element for Part 2, it kind of sounded a bit out of character for Caesar to run away from something he could've done some effort on, even without Underworld connections to help out, which is why I had Luffy "consume" him, but without exactly killing him. Caesar is, for lack of a better term, stuck inside Luffy's body and mind, but has enough "leeway" to advise Luffy on what to do and may even supply him with the Gas-Gas Fruit power if he wanted, and I wouldn't complain if he found a way out of his predicament in time for Part 2. It's kind of like a questionable Naruto story I know that has him absorb Orochimaru in a similar way, but without the questionable stuff.**

 **I had, for a time, considered of making this my own Germa 66 Luffy story for the future, but I'm on the fence right now about that because while Germa 66 may be rising in prominence like the Marines and Revolutionaries, we still don't if they'll play a big role for the rest of One Piece and it remains to be seen if they can be adapted for certain other scenarios from before Whole Cake Island, which is why this is a challenge story, and I'm still pondering about the possibilities for it if I took it up for myself. Trust me, I struggled for a time coming up with multiple full-length stories for One Piece and Fairy Tail. Until I get more information, I've got eleven stories from both anime/manga as well as Dragon Ball and Code Geass on my to do list. I'm just going to have to be on the lookout for what happens in the future.**

 **Last year, I had considered of writing challenge stories that would feature Luffy living with Nami's family for a time alongside Ace as well as Luffy going up against the Goa Kingdom during the three years between Ace's voyage and his own, but we don't know much about the Kingdom's current Queen for one example and the Brothers and Sisters thing was just something PortugueseRonaldo on FFN suggested, so it wouldn't exactly be original of me if I made a challenge of an idea that isn't mine. I think I can do interpretations of challenge stories that no else is taking at the time, like I did with Luffy's Search for Royal Brides, though. I really like Mister Grim's FFN challenge story of a Luffy who not only already knows about the Davy Back Fight, but uses it more than once for one example. I find it inspirational for my personal Pirate Luffy idea, you see.**

 **Also, I decided to do some work on my pat-reon rewards. From now on, to be a patron is a bit cheaper, and if you want a request for a one-shot or short story, you just have to go for a higher reward. And I'll also be posting this stuff at least a week before I put it on FFN and elsewhere. Hope you'll at least give it a chance.**

 **Anyway, just let me know what you all think of this challenge and if you want to uphold it.**


End file.
